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141.
This article reports the structural elucidation of the Alangium alkaloid, tubulosine (1) on the basis of systematic 2D-NMR analyses (DEPT, COSY, TOCSY, NOESY, ROESY, HMQC and HMBC). The data obtained allowed the unambiguous assignment of all proton and carbon signals in 1 for the first time. 相似文献
142.
C. Shobha Devi Penumaka Nagababu M. Shilpa Y. Praveen Kumar M. Rajender Reddy Nazar Md Gabra S. Satyanarayana 《Journal of the Iranian Chemical Society》2012,9(5):671-680
A series of four polypyridyl Ru(II) complexes such as [Ru(L)4(PIP)]2+ and [Ru(L)4PPIP]2+ where L is 4-amino pyridine and Pyridine (PIP?=?2-phenylimidazo[4,5-f] [1, 10] phenanthroline), (PPIP?=?2-(4??-phenoxy-phenyl) imidazo[4,5-][1, 10]phenanthroline) have been synthesized and characterized by elemental analysis, physicochemical methods such as UV?Cvis, IR and NMR spectroscopic techniques. The DNA-binding behavior of these complexes was investigated by electronic absorption titrations, fluorescence spectroscopy, viscosity measurements and salt-dependent studies. The experimental results indicate that all these complexes can bind to DNA through an intercalation mode, the DNA-binding affinities of these complexes follow the order [Ru(4-APy)4(PPIP)]2+(1)?>?[Ru(Py)4PPIP]2+(2)?>?[Ru(4-APy)4(PIP)]2+(3)?>?[Ru(Py)4PIP]2+(4). Noticeably, these complexes have been found to be efficient photosensitisers for strand scissions in plasmid DNA. Further, all four complexes screened for their antimicrobial activity indicate that the complexes show appreciable activity against Escherichia coli and Neurospora Crassa. In addition, in the presence of Co2+, the emission of DNA-[Ru(L4)PPIP/PIP]2+ can be quenched and recovered by the addition of EDTA, which exhibited the DNA ??light switch?? properties. 相似文献
143.
R.?L.?NaiduEmail author B.?Satyanarayana D.?R.?K.?Reddy 《International Journal of Theoretical Physics》2012,51(9):2857-2862
In this paper, we investigate Bianchi type-III universe which has dynamical energy density. We introduce three different skewness parameters along spatial directions to quantify the deviation of pressure from isotropy. We also assume that the skewness parameters are time dependent. The Saez-Ballester (J. Phys. Lett. A 113:467, 1986) field equations have been solved by applying a variation law for generalized Hubble’s parameter given by Bermann (Nuovo Cimento B 74:182, 1983). Some physical and kinematical properties of dark energy model are discussed. 相似文献
144.
Rao’s flag-transitive plane π of order 49 and π
t
, the plane obtained by transposing matrices of a representative set of π, has been studied. It is shown that π
t
is flag-transitive, π
t
is not isomorphic to π, and π
t
is obtained from π by replacement of a net of degree 25. Further, (1) the flag-transitive planes associated with 1-spread sets S
2b
and S
2a
in the classified list of translation planes of order 49 enumerated by Mathon et al, are respectively isomorphic to π and π
t
(2) The flag-transitive planes associated with the 1-spread sets of 0an* in the classified list of translation planes of
order 49 enumerated by Charnes et al are isomorphic to π and π
t
in some order. 相似文献
145.
A series of novel 1, 2, 4-triazolo isoquinoline derivatives (8a-8p) were synthesized starting from 2-phenylethan-1-ol derivative (1) in a 7 step synthetic sequence. The key step in the scheme involves 1, 3-dipolar [3?+?2] cycloaddition of azomethine imine and ethyl cyanoformate as unknown reaction protocol. We have demonstrated the hydrolysis of both ester and benzoyl group in a single step and the corresponding carboxylic acid derivatives were coupled with various amines to generate unknown 1, 2, 4-triazolo isoquinoline derivatives The structures of the compounds (8a-8p) were characterized by 1H NMR, 13C NMR and HRMS analysis. 相似文献
146.
Prashanth Kumar Kolluri Nirmala Gurrapu Praveen Kumar Edigi Subhashini N. J. P. Shravani Putta Surya Satyanarayana Singh 《Journal of heterocyclic chemistry》2019,56(12):3244-3256
In an attempt to achieve promising cytotoxic agents, a series of new (Z)‐3‐benzyl‐5‐((1‐phenyl‐3‐(3‐((1‐substituted phenyl‐1H‐1,2,3‐triazol‐4‐yl)methoxy)phenyl)‐1H‐pyrazol‐4‐yl)methylene)thiazolidine‐2,4‐diones 10 a‐n were designed, synthesized, and characterized by 1H NMR, 13C NMR, IR, and ESI‐MS techniques. These compounds synthesized from appropriate reaction procedures with better yields. All the novel synthesized compounds 10a‐n were evaluated for their cytotoxic activity against the MCF‐7 cell line (Human breast cancer cell line) at different concentrations of 0.625, 1.25, 2.5, 5, and 10 μM, respectively. The cytotoxic evaluation assay is presented in terms of IC50 values and percentage cell viability reduction compared against standard drug cisplatin. Among all novel synthesized compounds 10a‐n , some of the representative analogues particularly 10g and 10e exhibit remarkable cytotoxic activity with IC50 values 0.454 and 0.586 μM, comparable to that of the standard drug cisplatin, and some analogues 10d , 10f , 10k, and 10m also have shown significant activity. 相似文献
147.
148.
Phase-transfer-catalyzed, highly versatile, and high-yielding protocol for the synthesis of 2,4,5-triaryl-1H-imidazoles was developed through response surface methodology (RSM). The effects of different solvents, reaction paths, and phase-transfer catalysts (PTCs) in different concentrations were envisioned. Three independent variables (catalyst, catalyst loading, and solvent volume) identified by one-factor-at-a-time (OFAT) study were screened through full factorial design at two levels. The analysis of variance results suggested the significance of catalyst PEG400 and solvent glacial acetic acid at 5 h reaction. The optimum reaction conditions suggested by the RSM were the use of PEG400 (10.61 mol%) and glacial acetic acid (10.71 mL) for 5 h cycloocondensation. The experimental yield of 4,5-diphenyl-2-nitrophenyl-1H-imidazole (97%) was in agreement with predicted yield (97.5%). 相似文献
149.
Katta Muralikrishna Gavireddy Chaithanya Kumar Vavilapalli Satyanarayana R. Sudheer Kumar Jhillu Singh Yadav 《Tetrahedron letters》2018,59(48):4209-4212
A convergent and highly stereoselective formal synthesis of Pellasoren – A is described. The salient features of the synthesis are the utilization of enzymatic desymmetrization, Crimmin’s non-Evans syn aldol, Lindlar’s and Wittig reaction. 相似文献
150.